Synergistic insecticidal compositions



United States Patent 2,990,315 SYNERGISTIC INSECTIOIDAL COMPOSITIONSHoward A. Jones and John A. Garman, Baltimore, Md., and Berton C.Dickinson, Lyndonville, N.Y., assignors to Food Machinery and ChemicalCorporation, New York, N.Y., a corporation of Delaware No Drawing.Original application Mar. 24, 1955,.Ser. No. 496,596. Divided and thisapplication Oct. 17, 1958, Ser. No. 767,783

5 Claims. (Cl. 167-22) This invention relates broadly to insecticidalcompositions, and more particularly to insecticidal compositionscontaining an organic carbamate acid derivative and 0,0- dimethyl S-(1,2 dicarbethoxyethyl) dithiophosphate, hereinafter referred to asMalathion. More particularly, this invention relates to synergisticinsecticidal compositions of these compounds wherein the insecticidalelfectiveness of each component is enhanced by the presence of the otherto produce an unexpected combined effect.

When two or more substances in combination show an unexpectedly highactivity, as for instance, insecticidal activity, the resultingphenomenon is called synergism. The mechanism of synergism is by nomeans understood. It is, in fact, quite probable that it diifers withdifierent synergistic combinations. The term synergism can be defined,however, as a cooperative action which is encountered in combinations oftwo or more biologically active components in which the combinedactivity of the two components exceeds the sum of the activities of thecomponents when used alone. The insecticidal activity of the mixedcomponents cannot be predicted from known values of the individualcomponents, but is unpredictable and depends on the individual activityof neither.

It is an object of this invention to provide insecticidal compositionsof enhanced killing power. Another object of this invention is toproduce novel compositions down and killing properties of individualtoxicants. A further object of this invention is to provide compositionsincluding a relatively toxic phosphorus containing insecticide in whichsuperior insecticidal activity is obtained because of the synergisticeffects, but in which the ultimate toxicity to warm-blooded animals isgreatly reduced 7 because of the lower concentrations of the phosphoruscompounds required when used, in combination with the.

relatively less toxic carbamates. Other objects and-advantages of theinvention will become apparent from the description of the invention setforth below.

According to this inventio'nfthe'r'e are provided synerI- gisticinsecticidal compositions comprising 0,0-dimethylS-(1,2-dicarbethoxyethyl) dithiophosphate, hereinafter called Malathion,and an organic carbamate ester having the following general formulaNCOOR H wherein R is selected from the group consisting of ethyl andisopropyl radicals and R is selected from the group of 2-chlorophenyl,3-chlorophenyl and 4-chlorophenyl radicals. These carbamates may beprepared as described in copending application Serial No. 812,113, filedMay 11, 1959'.

The synergistic insecticidal compositions of this invention may be usedon a wide variety of insect and mite species, but are particularlyeffective against such insects as the two-spotted spider mite, harlequinbug and Mexican bean beetle. The combinations are highly efiective andeconomical to use for such large-scale insecticidal requirements as thecontrol of truck crop, forage crop and orchard insects.

The synergistic compositions of this invention can be formulated asaqueous emulsions, as dry or wettable powders, as solutions or in anyother suitable vehicle. The insecticidal compositions can be utilized assprays, as dusts, as aerosol mixtures, insecticidal coatingcompositions, and as residues. In general, they can be applied bymethods commonly used for {control or eradication of insects, mites andthe like. Thus these insecticidal compositions can be formulated withsolvents, diluents and carrier media, adhesives, spreading, wetting andemulsify ing agents and other ingredients.

The relative proportions of the active ingredients as well as inertcarriers, solvents, dispersants 'and the like may vary within widelimits.

Thus the relative proportion (ratio) of the Malathion to the carbamateester canrange from 20 parts of the former per 1 part of the latter to 1part of the former per 40 parts of the latter and preferably about 1part of the former to about 2 parts of the latter. 1

The quantities of the component toxicants in the final insecticidalcompositions can range from 0.01% to 25.00% for theMalathion and from0.05 %v to 50.00% for the carbamate, and preferably from 0.10% to 10.00%for the Malathion and from 0.10% to 25.00% for the carbamate.

The procedures of the testing methods are described below. The detailsof the test experiments including the *type of formulation and mode ofapplication or closing,

- The test methods used are described as follows: containing compoundscapable of synergizing the knockf DUST TOWER METHOD 7 This generalmethod is described in the following reference, Moore, J. Econ. But. 43,No. 2, 188-190 (1950).

- The dusing apparatus consists of averticalglass cylinder, 34 incheshigh and 8.5 inches in diameter, into which the appropriate dust sampleis discharged through a small hole in the center of the cover, by meansof a small laborastopper through which pass the air inlet and dustoutlet tubes, both of which are made of A inch diameter copper tubing.At the outer end of the air inlet tube is a trigger valve that serves asa control for dispensing the dust. The inner end of this tube reachesnearly'to the bottom of the beaker. The end of it is sealed but, alongthe sides, seven 0.032 inch holes are drilled at, irregular intervalswhichserve as air inlets. Such an arrangement causes pronouncedturbulence of the dust and thus insures exhausting the complete samplefrom the beaker. The dust outlet tube forms an arch from the top of thebeaker to the top of the glass dusting tower.

After discharge of the sample into the tower, there is allowed a2-minute settling time before removal of foilage or insects beingtreated. A weighed metalplate'is placed in the tower each time a test ismade, and by weighing the amount of dust deposited on it, it is thenpossible to calculate the amount applied per acre. p g 7 Because ofday-to-day variations in the results obtained 7 by this test method,comparisons among the individual Mexican bean beetle-In tests using thisinsect, bean foliage dusted then infested with fourth instar Mexi canbean beetle larvae. These were allowed to feed for 24 hours, thentreated foliage was replaced with untreated. Mortality records were madeat 48 hours.

4 S-(1,2-dicarbethoxyethyl) dithiophosphate, said ingredients beingpresent in the ratio of about 4 parts of said carbamate ester to about 1part of said dithiophosphate.

4. Synergistic insecticidal compositions comprising 0,0-

The results of the data summarized in Table 1 demonstrate the markedsynergism of the insecticidal compositions of this invention on a.number of insects.

This application is a division of copending application Serial No.496,596, filed March 24, 1955, now abandoned, which is acontinuation-impart of Serial No. 427,374, filed May 3, 1954, nowabandoned. r

We claim:

l. Synergistic insecticidal compositions comprising 2- chlorophenylNethyl carbam ate and 0,0-dimethyl S-(1,2- dicarbethoxyethyl)dithiophosphate, said ingredients being present in the ratio, of about 2parts of said carbamate ester to about 1 part of said dithiophosphate. 7

2. Synergistic insecticidal compositions comprising 4- chlorophenylN-ethyl carbamate and 0,0-dimethyl S- (LZ-dicarbethoxyethyl)dithiophosphate, said ingredients being present in the ratio of about 2parts of said car:

bamate ester to about 1 part of said dithiophosphate.

3. Synergistic insecticidal compositions comprising 3= ehlorophenyl:N-isopropylcarbamate and 0,O -dimethyl Two-spotted spiderl mite.Intests on two-spotted 5 dimethyl S-(l,2-dicarbethoxyethyl)dithiophosphate and mites, the were confined to the upper surfaces of anorganic carbamate having the general formula potted bean plants by aTanglefoot ring. The bean V plants were placed in the glass tower andthe mites direct- Y e dusted. Mortality readings were taken in 24 hours.ICOOR 7 Only adult mites were used in determining mortality 10 H counts.p p wherein R is selected from the group consisting of ethyl Peaaphid-Pea plants were infested with pea aphids and isopropyl radicalsand R is selected from the group and direct-dusted. Mortality readingswere taken at 24 47 consisting of 2-chlorophenyl, B-chlorophenyl and4-chlohours. 4 x e Y rophenyl radicals, wherein said components arepresent Harlequin bug-The foliage was dusted, then infested in the ratioof about 2-4 parts of said carbamate per part Wlfl]. harlequin bugs.Mortality counts were taken in 24 of said dithiophosphate. hours. ,5.The method of killing insects which Comprises ap- Squash bug.For thistest squash leaves were collected plying to the insects and theirhabitat a synergistic insecin the field and the cut ends of the stemwere wrapped in ticidal composition comprising 0.0 dirnethylS-(1,2-dicar moist cotton. Individual leaves were then placed in 3.5bethoxyethyl)-dithiophosphate and an organic carbamate inch Petri dishesand dusted as described above. Each having the general formula treatedleaf was then infested with 10 last instar squash R4 bug nymphs and thecovers of the Petri dishes were re- NCOOR,

, placed. At the end of 24 hours the treated leaves were removedandfresh untreated leaves were introduced into 25 H the dishes." .Mortalitycounts were taken after the bugs wherein R is selected from the groupconsisting of ethyl hadbeen on the untreated leaves for 24 hours. 7 andisopropyl radicals and R is selected from the group I Table 1 i R aNCOOR' Carbamato Phosphate Bate Mortality 7 (Lbs./ Test Method TestSubiect at 24 Hrs. Dust Dust Acre) (percent) B. R 00110., Name Cone,Percent percent Ethyl 4-Chloro phenyL. 1.0 50.8 Dust Tower. Squash Bug 0.Malathion 0.5 46.1 do do 0 Dodo- 1.0 Mao 0.5 51.2 do- 100 Do2-Ghloropheuyl; 1 9. 6 Twospotted spider Mite 0 Malathton 0. 5 7. 2 do-41 Do- 1 do 0.5 6.2 do 97.5 IsopropyL. B-OhlorophenyL 1 9. 6 MexicanBean Beet1e 0 Malathion. o. 5 1o. 2 do- 25 Dodo 1 .d0 0.5 8.3 60 Do do 136.6 0 Malathion 0. a as. 0 D .do 1 o 0.5 30.5 90 Ethyl".-.4-Ch1oropheuyl. 1 8.0 5 Malathion. 0. 5 6. 4 29 .do 1 do 0.5 7.0 1004-Methy1phenyL 1 9. 4 1 Malathiou 0.5. 9.3 as .do 1 do; 0.5 a 6.7 100A-Nitrophenyl..- 1 V 8. 8 1 Malathicru 0. 5 9. 3 88 Do do 1 -do 0.5 7.6100 IsopropyL. 3-Ch1orophenyL. 1.0 32.7 0 Malathion. 0.25 27.6 0 Do do1.0 o 0.25 27.9 100 consisting of 2-ch1orophenyl, 3-chlorophenyl and4-chlorophenyl radicals, wherein said components are present in theratio of about 2-4 parts of said carbamate per part of saiddithiophosphate.

References Cited in the file of this patent UNITED STATES PATENTSJelinek April 11, 1950 Gysin May 25, 1954 OTHER REFERENCES

1. SYNERGISTIC INSECTICIDAL COMPOSITIONS COMPRISING 2CHLOROPHENYLN-ETHYL CARBAMATE AND O,O-DIMETHYL S-(1,2DICARBETHOXYETHYL)DITHIOPHOSPHATE, SAID INGREDIENTS BEING PRESENT IN THE RATIO OF ABOUT 2PARTS OF SAID CARBAMATE ESTER TO ABOUT 1 PART OF SAID DITHIOPHOSPHATE.